Detection method for combustion misfire

PROBLEM TO BE SOLVED: To properly detect a combustion misfire by utilizing the first complex input feature signal as a feature signal to detect a continuous misfire, as well as to detect an independent misfire. SOLUTION: A sensor signal ts(n) is inputted to the input ends of signal processing and feature extraction stages, and signal formation takes place in the stages through a dynamic correction process. Also, a signal modulation stage extracts a primarily assigned feature signal q11(n). This feature signal q11(n) passes a reference signal generator, and the magnitude thereof is used for detecting a continuous misfire through a comparison with a threshold value, thereby determining a cylinder giving a misfire on the basis of a phase. In a prefilter, a derived signal qrs(n) for detecting an independent misfire is generated on the basis of the formation of an average value within a travel screen. As a result, a combustion misfire can be properly detected. COPYRIGHT: (C)1997,JPO